package hello;

import java.util.Scanner;

public class Text5 {
	public static void main(String[] args) {
		/*int i,j,s;
		for(i=1;i<=9;i++){
			for(j=1;j<=9;j++){
				s=j*i;
				if(j<=i)
				System.out.print(j+"*"+i+"="+s+"\t");
			}
			System.out.println("\n");
		}*/
		
		Scanner in=new Scanner(System.in);
		System.out.println("请输入一个数");
		int k=in.nextInt();
		int j,s=1;
		for(j=1;j<=k;j++){
			s*=j;
		}
		System.out.println(s);
	 }
	}
